Gang cutters for paring log protuberances



Aug. 13, 1957 T. w. NlcHoLsoN 2,802,494

GANG CUTTERS FOR PARING LOG PROTUBERANCES Filed sept. 15, 1955 INVENTOR. 7//0/14/45 W /V/@/OLHOA/ N2 ,Madam United States Patent GANG CUTTERS FOR PARING LOG PROTUBERANCES `Thomas' W. Nicholson, Auburn, Wash. Application September 13, 1955, Serial No. 533,996 11 Claims. (Cl. `144--134) This invention relates to a vgang lcutter for paring log protuberances and is particularly useful in association with a log barking machine inwhich a plurality of barker tools are spaced circumferentially about a log, and the log and mounting for such .tools are rotated relatively and moved axially simultaneously so that the barker tools follow a spiral path around Athe log.

It is a principal object of the present invention to provide such a gang cutter which conveniently -can be constructed as an attachment for a' log barker, such for example as a rotary ring "barker which may be of the type disclosed in my copending patent application Serial No. 407,361, tiled February 1,1954. To enable a gang cutter to be attached to such a barker it is an? object to makeit f of compact construction A further object is to provide such will remove from a log protuberances vahead ofthe barker tools to a diameter which will'enable the barker to handle logs of maximum size and so that its capacity will not be curtailed by projecting limb stubs', knots, bumps, Yother irregularities and excessively ared butts.

lt is an object to provide such a gang cutter which will I be automatic in operation and will rremove protuberances from a `log quickly and efficiently.`

While the gang cutteris designed rr'uggedly to witha 'gang cutter which Y "ice Figure 3 is a perspective view of a fragmentary portion No. 407,3 62. A brief description of such mechanism here stand severe shock loads, it has `anibbling action so as to v avoid imposing large `surgesin power demand on the barker drive mechanism, and byremoving ,such protu'berances in the form of small chips and shavings the material thus removed can be disposed of readily.

In general, the gang cutter includes a cutter bit carrying ring encircling la 'log :and operated in synchronism with barker tools for relative n :tovenlent circumferentially of Y the log. Such ring carries a multiplicity of cutter bits projecting `a short distance inward therefrom `and such ring is ahead of the barking tools so that the cutters will engage protuberances on `the log before they reach the barking too'ls'. The ycutting bits are preferably of fc'hiseltooth shape having substantial side rake' and end rake, and presenting an acute cutting angles to themlog protuberances.A Conveniently, ttlte-lutt'bit carrying ring can .take the form of an annular mounting plate disposed in a plane perpendicular to a log moved through it, and the bits can be formed integrally with the leading face of such annular plate as ribs inclined relative to radii of the plate passing through such ribs, respectively, to dispose their inner cutting ends foremost, and such ribs may oe of substantially triangular cross section, arranged to present a leading side and having a trailing angle. The preferred types of cutter bit carrying ring and cutter bits are shown in the accompanying drawings.

Figure 1 is an elevation view of a rotary ring log barker equipped with a gang cutter of the present invention, parts of the barker being broken away.

Figure 2 is a detail sectional view through a portion of the barker and gang cutter, taken on line 2-2 of Figure 1.

will therefore suiiice to illustrate a typical application of the present gang cutter'invention.

To enable my gang cutter to operate on a log it is necessary that a log and the cutter bit carrying ring be moved simultaneously relatively rotatively and axially, so that the log will pass through the ring. While it makes no difference whether the log be moved through the ring, or the ring moved over the log in an axial direction, the barker illustrated in Figure `l shows a log carried through the ring by rotative ribbed rolls 1- driven by chain 1, against which the log L is held by hold-down wheels 10. The log is moved lengthwise through the barker and gang cutter by rotation Vof such rolls.

Moreover, while it is immaterial how ,relative rotation of the cutter bit carrying ring and log is accomplished, the log may be held against rotation by the pressure of wheels 10 Vpressing the `log against the ribbed roll 1, and the barking tools and gang cutter can be rotated. Such a barker may incorporate the ring 2 mounted for rotation in a stationary ring 20, which is supported by s'lidesx21 4carried by opposite' ends of an upper cross beam 22 and :to rotate such ring relative to stationary ring 20.

As shown in "Figure 2, the ring 2 includes two `flanges 3 and 30 which are spaced apart yaxially of the ring a substantial distance to accommodatebetween them a plurality of swingable arms, preferably four in number, the inner .ends of which carry barker tools 4` Which `preferably are ,scraper plates. Swinging of the barker tool carrying arms is controlled by air cylinders 34 pivotally supported on the ring anges 3 and 30 by pivots 35.

`,As shown in `Figure 2, the stationary ring 20 is engaged by wear plates 77 secured on opposite sides of va channel portion of rotary ring 2,` These Wear plates, which may be of brass, are engageable with opposite sides of an ,inwardly' projecting portion of the stationary ring to resist thrust kforces directed axially -of the ring. Such plates are in communiaction with ,theV annular space 73 to which lubricant may be supplied for ,lubricating the slidingt between the vStatoifluy `ringand the plates-V Between the' Qstationary ring 20 and the ,ilanges of `the U-,shaped recess ,in 'ringQZ are mounted annularjlubricantseal ,rings 781sealing thlubicant in the annular space 7 3'. It will be evident that this construction provides a very stable support and accurate guide for rotary ring 2, and such ring itself is of sturdy construction and is therefore Well adapted to carry the gang cutter of the present invention.

The gang cutter incorporates the cutter bit carrying ring which, as shown, is preferably formed as an annular plate of considerable radial width. In this plate are provided attaching apertures 101 arranged to register with cooperating apertures `in the rotary ring 2 of the barker. Securing bolts 102 extend through the apertures 101 in the gang cutter ring 100 and the apertures in the barker ring 2 for rigidly attaching the gang cutter to the rotary barker ring. t

The gang cutter incorporates a multiplicity of cutter bits 103 carried by andprojecting inwardly from the bit carrying ring 100 substantially chordwise of the ring and spaced circumferentially around such ring, preferably equidistantly. A multiplicity of Asuch cutter bits is provided so that the cutter bits will engage any given protuberance on a Alog in rapid succession to, nibble it away, similar to the action of a broach, so,as.to minimize Yshock loads on the bits and to avoid large surgesin-power demand of the barker caused byk addition of the protuberance cutter toit. j Y Y As shown in the several figures of the drawings the bits 103 project a very short distance inward from the ring 100 and therefore are very strong. These bits are of chisel-tooth shape having an acute, rather small cutting angle, and a substantial amount of bottomrake and side rake to afford ample clearance for the cutting edge ,despite the rather rapid axial movement of the log as .compared to the relative rotative movement between the log and cutter carrying ring. In fact, the trailing ,face Vofthe bit, as

log therethrough, and a multiplicity of bits carried by said ring, spaced circumferentially" about said ring at substantially equal intervals fnd projecting inward therefrom substantially chordwse of said ring.

7. Gang cutting mechanismrfor paring log protuberances comprising log supporting means, an annular cutter mounting plate disposed in a plane perpendicular to the length of a log carried by said log supporting means and of a sizeto receive therethrough a logcarried by said log `supporting means, means operable to effect relative rotative and axial movement simultaneously of said plate and a log on said log supporting means, and a plurality of ribs on the leading face ofsaid plate having shown best in Figure 3, preferably is of substantially triangular shape.

, It is important that the cutting bits be mounted on 'the ring 100 extremely securely and rigidly, and such construction may be accomplished conveniently by forming the cutting bits as projecting ends of ribs 104 formed integral with andprojecting from the leading face of the annular plate 100. These ribs are inclined relative to radii passing through them respectivelyV to Vdispose their inner bit vends foremost. The inclination of such ribs affords a largetop rake and reduces the. cutting angle and forms a toolV angle of approximately forty-five degrees.

In order :that Y the trailing face of the bit may be of triangular shape as preferred, the ribs 104 are preferably also of triangular cross section'and are arranged to present a leading side 105'and a trailing angle 106. The stubby,

inwardly projecting ends of such ribs therefore present a rugged chisel bit arranged 'so that successive bits will pare away small particles or shavings ofany log protubervance, whetherl a branch stub S, as shown in Figure l,

or a bump B, or-'even a are'd butt, so that the, ,log

will pass through the rotary barker ring unquestionably vand cannot become jammed in it or against it to disrupt operation of the barker. I claim as my invention: y `1. A gang cutter for paring log protuberancesj comprising a cutter bit carrying ring of a size to receive a log therethrough, and a plurality of bits iixedly secured 'to said ring in circumferentially spaced relationship and projecting inward therefrom substantially chordwse of said ring.

2. The gang cutter defined in claim 1, in which the 4bits are chisel-tooth bits.

3. The gang cutter defined in claim 1, in'which the bits are chisel-tooth bits having'a tool angleof approximately forty-five degrees.

4. The gang cutter defined in claim l, inV which the Vbits have substantial side rake and bottom rake.

`5. The gang cutter defined in claim 4, in which thev bottom of the bit is of substantially triangular shape.

6. A gang cutter for paring log protuberances comi i' 'prising a cutter bit carrying ring of a size to receive a ends projecting inwardly beyond the inner periphery of said plate, inclined relative to radii of said plate passing through the respective ribs to dispose their inner ends foremost in the direction of relative rotation of said ring and a log carried by said log supporting means, and the endsv of said'-k ribsf projecting .inward 'beyond ythe vinner periphery of said plate Abeing Vformed as cutting bits.

8. The gang cutteryrn'echanism defined in claim 7, in `which the ribs ,are integral withthe plate.

9. The gang cuttermechanism defined in claim 7, in which each ribhas av leading side of van axial width substantially greater than `the `axial width of `thel portion of the'bit, behind such leadingside'.

1.0. The gang cutter'mechanism defined `in claim `7, in which the ribs aregof substantially triangular cross section having -a leading side and a trailing angle.

"11. Gang cutting mechanism for paring log protuberances comprising log supporting means, an annular cutter mountingfplat'e' disposed in aV plane-perpendicular to the lengthof a log carried by said log-supporting means and of a size to receive therethrough a, log ,carried by said log supporting '"means, means roperable to elect relative rotative and axial movement `simultaneously of said plate and a log onwsaid logy supporting means, and a pluralityrof -ribs on-the leading face of said plate eachof substantially triangular crosshsection with 'a vleading side, `having ends projecting inwardly beyond ther inner periphery of said plate, inclined relative A to radii of said plate passing through the respective ribsv to dispose Atheir inner ends foremost in the direction of relative rotation of said ring anda log carried by `sa'idrlog supporting means, and the .substantially triangular ends of said ribs projecting inward beyond the inner formedl as chisel-tooth bits having a tool angle of approximately forty-five degrees.

ReferencesiCvited in the leof this patent UNITED STATES' PATENTS V737,646 Moreau sept. i, 1903 827,747 Moreau A..J Aug. 7, 1906 2,109,414 Deite'rs et a1. Feb. 22, 193s `2,482,392 Whitaker Sept. 20, 1949 i FOREIGN I A'rENTs Great Britain of 1865 periphery of said plate being- 

